SINGAPORE - China on Sunday rejected US demands to stop all reclamation works in the South China Sea, saying it was exercising its sovereignty and using the outposts to fulfil international responsibilities.

Admiral Sun Jianguo, deputy chief of the general staff department in the People's Liberation Army, told a security summit in Singapore that "the situation in the South China Sea is on the whole peaceful and stable, and there has never been an issue with the freedom of navigation."

"China has carried out construction on some islands and reefs in the South China Sea mainly for the purpose of improving the functions of the relevant islands and reefs, and the working and living conditions of personnel stationed there.

China insists it has sovereignty over nearly all of the South China Sea, a major global shipping route believed to be home to oil and gas reserves, but rival claimants accuse it of expansionism. Vietnam, the Philippines, Malaysia, Brunei and Taiwan also have varied claims over islets and reefs in the area.

"When dealing with maritime disputes with relevant neighbouring countries, China has always kept in mind the larger interest of maritime security," Sun told the annual meeting known as the Shangri-La Dialogue.

"In spite of the sufficient historical and legal evidence and its indisputable claims, rights and interests, China has exercised enormous restraint, making positive contributions to peace and stability of the region and the world at large."

Beijing 'out of step'

Sun was speaking a day after US Defense Secretary Ashton Carter demanded an immediate end to all reclamation works by claimants and said Beijing was "out of step" with international norms with its behaviour in disputed waters.

"First, we want a peaceful resolution of all disputes. To that end, there should be an immediate and lasting halt to land reclamation by all claimants," Carter said on Saturday at the same forum with Sun and his delegation in the audience.

"We also oppose any further militarisation of disputed features," he said.

He acknowledged that other claimants have developed outposts of differing scope and degree, including Vietnam with 48, the Philippines with eight, Malaysia with five and Taiwan with one.

"Yet, one country has gone much farther and much faster than any other.